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F10 / F11 (2011 - 2016) The sixth generation of the BMW 5 Series Sedan (F10) was produced from 2011 - 2016 with LCI updates arriving in 2014. In the US BMW offered a hatchback 5 Series Gran Truismo (F07) and the rest of the world also go a Station Wagon/Touring version F11.

When I was picking the options for my F10 I did a lot of research on the ACC. There were several posting that stated that you cannot use a radar detector with the ACC activated.

I just completed a 2,100+ road trip with my Valentine One radar detector mounted on the front windshield for the entire trip. There were no issues with the ACC interfering with the radar detector. Perhaps other brands of detector do have issues.

The issue is that the radar detector adapts to the presence of radar interference. So if you operate another radar device near your detector it will diminish sensitivity on the band they both use.

In my car for instance, if I switch on the blindspot monitor, it reduces K band sensitivity. The blindspot monitoring doesn't cause the radar detector to go off, it just introduces background k band noise, which means it will only detect louder k band signals (e.g. When the cop is really close). Knowing this, I switch it off on long drives since I know that outside the big cities, K band is widely used.

This interference/noise issue is always present. The Blindspot radar causes it, the ACC causes it, and even running 2 detectors at the same time can cause it.

If you have a really powerful detector like the V1 or the 9500ci, you may still find it alerts you on K Band, but even if you find the diminished range acceptable, there is a bigger issue: the background noise basically kills ability to detect short blips (e.g. When they use instant on mode). So you will be vulnerable to devices with that functionality, whereas a clean system with no background noise would be fine.

It all boils down to how fast you drive. If radar becomes a mission critical application then you need to be able to switch off the vehicles radar systems. ACC cannot be switched off.

The issue is that the radar detector adapts to the presence of radar interference. So if you operate another radar device near your detector it will diminish sensitivity on the band they both use.

In my car for instance, if I switch on the blindspot monitor, it reduces K band sensitivity. The blindspot monitoring doesn't cause the radar detector to go off, it just introduces background k band noise, which means it will only detect louder k band signals (e.g. When the cop is really close). Knowing this, I switch it off on long drives since I know that outside the big cities, K band is widely used.

This interference/noise issue is always present. The Blindspot radar causes it, the ACC causes it, and even running 2 detectors at the same time can cause it.

If you have a really powerful detector like the V1 or the 9500ci, you may still find it alerts you on K Band, but even if you find the diminished range acceptable, there is a bigger issue: the background noise basically kills ability to detect short blips (e.g. When they use instant on mode). So you will be vulnerable to devices with that functionality, whereas a clean system with no background noise would be fine.

It all boils down to how fast you drive. If radar becomes a mission critical application then you need to be able to switch off the vehicles radar systems. ACC cannot be switched off.

I, too, have a V1. While your concerns are clearly theoretically valid, the question then becomes how often have you actually driven past a police car with a radar emitter with your ACC on without having been warned by your radar detector. Maybe the warning sounds a half mile in advance rather than a full mile but this is still enough warning. I can't remember driving past a radar trap with both my ACC and blind spot detector on and the V1 not picking up the police radar. I do a fair amount of long distance driving on radar patrolled interstates and keep careful tabs on these occurances.

So, while interference is likely to some degree, the issue is whether or not the amount of interference has any practical implications. I have been using the combination of ACC and the V1 since I got my 650i with ACC in 2005 and have never had a problem or noticed any practical degredation of the performance of my V1.

In addition, when driving on long stretches in isolated areas on the interstate with the blind spot detection always on I never get false positives in the V1. It is totally silent. When driving through populated areas there are very frequent false positives, but I have no reason to suspect these have anything to do with the blind spot detector. However, I have not done a formal statistical analysis of the frequency of such false positives with the blind spot dectector switched on and off. However, the multiple warning variables of the V1 are so good that it is usually easy to separate true from false positives.

Are you also saying that when the ACC is turned off it's radar function is still operative? I guess this would make sense because the collision avoidance system might still be on. However, the collison avoidance can also be turned off. It is true that the cruise control cannot be used without the active feature, ie it cannot be set to function as a non active cruise control.

Even so, from your previous posts you indicated that you never use the ACC even on the SUV your wife has when you drive it. So, do you actually have any real world experience driving through radar traps with both the ACC and the V1 turned on?

My father's Toyota has laser cruise and when its raining, you can switch down to regular cruise because the radar sensor doesn't work well in the rain

My ACC works very well in the rain. The only problem is when the emitter in the front becomes caked with ice, snow, or slush. The BMW ACC is radar. Is the Toyota ACC laser? Maybe that's the difference.

My ACC turns itself off and gives a warning when it ceases to function. It cannot be set to function as a non active cruise control. I think it would be a good idea to have that option. Of course, if the driver made a mistake and forgot the active part was turned off he might crash into the car in front of him. Maybe that's why BMW doesn't offer that option. BMW is extremely safety conscious.